Mixing machine



1933- D. A. DUCHARME Er AL 8,377

MIXING MACHINE Filed May 51, 1930 2 Sheets-Sheet l INVENTORS @mJkQ fiwaZwp/w By Attorneys,

1933- D. A. DUCHARME ET AL ,37

MIXING MACHINE Filed May 51, 1930 2 Sheets-Sheet 2 INVENTORS nd]? .fla/rzfia J By Attorneys,

m v w w Patented Dec. 5, 1933 UNITED STATES PATENT OFFICE MIXING MACHINE Application May 31, 1930. Serial No. 458,176

Claims.

This invention relates to mixing machines, and aims to, provide certain improvements therein.

The invention is particularly directed to machines of the type of the well-known Banbury 6. mixer which usually comprises two rotors mounted in semi-cylindrical troughs, the rotors being adapted to smear the product to be mixed against the cylinderwalls. The feed in this type of mixer is usually arranged at the top of the troughs and 10 between the latter. It customarily comprises a .hopper for receiving the products to be mixed which is'connected with the troughs by a neck, a weight being provided to press the products downwardly through the neck into the troughs.

lni-plasticating bakelite from the original pow dery-form it has been customary to pass the entire batch of powder repeatedly between two mill rolls, the operation being-repeated a sufiicient number of times to. obtain correct plasticity of the mass by the pressure of heat developed during the rolling operations. 'We have discovered that under certain conditions we can plasticate bakelite compounds in a machine of the Banbury type wherein the material is ordinarily sent but once through the machine, .a portion of the batch being operated upon until the plasticity required is attained, whereupon it. is discharged. As the process is approximately a continuous process, the bakelite material.is placed-in the hopper, and as the quantity in .the cylinders-is reduced, feed takes place from the hopper to the cylinders. As the operation involves considerable heat in and around the machine, themass about to be fed is apt to become very sticky, and as it is not subjected during its 3,5 progress tolthe cylinders to pressure, this preliminary heating not only interferes with the feed, but produces in the final batch, portions which 7 are of different chemical or physical characteristics. -We have found that while maintaining the bakelite-massin a substantially cool condition untilitis ready for introduction to the cylinders and is there acted upon'by both heat and pressure,we.not onlyobtain muchcetter feeding operation-by reducing its stickiness, but also obtain amoreunifcrm batch. This is accomplished according to the present invention by cooling that part of the materialwlfich is in thehopper neck through which the material passes prior to its entrance into the cylinders. At this point the 5() .material isin sufflcient-proximity-to the cylinders 55.,tion whereinheat conduction from the wall of the machine is avoided as far as practicable. It is not necessary to cool the complete hopper walls although it is in some instances advantageous to cool the feeding weight which presses down on the top of the material and tends to press it through the neck.

The pressure exerted by the feeding weight is, of course, very light as compared with the pressure in the cylinders, the feeding weight being designed merely to assist in feeding.

In the drawings, which illustrate several forms of the invention,-

Figure 1 is a vertical section of a mixer of the type described, taken through the rotors and through one end of the neck opening.

Fig. 2 is an enlarged sectional view oi the water cooling system which we prefer to use.

Fig. 3 is a section taken on the-line 33 in Fig. 2, partly broken away.

Fig. 4 is a horizontal section. .75

Fig. 5 is a sectional view of a modified form.

In proceeding to utilize our invention, we prefer to make use of the standard form of Banbury mixer, making only such modifications as may be necessary, without changing the design of the machine. We will hence first describe the inven tion as thus constructed with reference to Figs. 1 to 4.

In these figures letA represent the standard Banbury mixer, having troughs B and C of semicylindrical form which are usually water-jacketed, as shown. In these troughs work rotors E andF which are so shaped as to smear the product to be mixed against the cylindrical walls of the troughs in such manner that the product is passed freely from one trough to another and back again. Leadingfrom the top of the troughs and mid-way between them is the usual neck G, which ordinarily is a plain rectangular passage formed in the same casting as the trough and usually constructed of a length which is similar to that of the rotors. On the top of the neck section G is a hopper H in which the products to be mixed are loaded, and at the rear. of the hopper and mounted in line with the neck is a feed weight I car ied upon a rod J, by which it may be retracted by mechanism, such as a piston or the like mounted at the top of the machine, and which is not shown, being unnecessary to an understanding of the present invention.

We preferably provide such a machine with a cooling liner, such as is shown in detail in Figs. 1 to 4. In the preferred form which is illustrated, this liner comprises a casting K having a smooth interior, and having at its top a funnel-shaped 110 flange L, while at its bottom it is provided with a flange M of any appropriate shape. the two flanges extending from the body portion of the casting outwardly, and having such dimensions that they fit the interior of the neck G. There is left by this construction, surrounding the entire body portion K (or some considerable part of it), a space N which lies between the body portion and the inner side of the neck G. This space is utilized to accommodate a water-jacket O, the pre-. cise shape of which is immaterial, but which is shown in the drawing as extending substantially entirely around the body K of the liner. This water-jacket may be formed in one, two or more sections, but in the preferred form it is constructed in one section, as best seen in Fig. 4. This section is rectangular, and is provided with inturned flanges P P at the top, bottom and sides, which after assembly contact with the outer wall of the body portion K to form a closed water passage Q. Sheet metal is best used for the waterjacket, and this is united to the body K by welding, brazing, or any other suitable method.

In the preferred form of the invention we utilize a construction in which a liner is heat insulated from the neck. By this means the transfer of heat to the liner from the neck is considerably minimized so that the work required of the cooling water is reduced. In certain instances the water may be dispensed with or considerably decreased in volume. The form of insulation which we prefer is that of an air spacewhich may be more or less confined. In this respect, if water is not being passed through the liner, the chamber Q constitutes one such space, but in any event we prefer the construction in which the jacket 0 does not contact with the interior wall of the neck but is separated by a space E preferably extending completely around the liner. Obviously, instead of an air space, heat insulation may be secured by backing the space with any insulating material.

The liner is preferably of cast construction, and in order that it may be adequately secured to the interior of the neck G, it is formed with a series of spuds or projections R which are tapped and adapted to receive set screws S, S passing through the exterior of the neck, as best seen in Figures 1 and 2. Ordinarily the jacket 0 will be provided with openings fitting over the spuds and welded thereto. These spuds do not materially interfere with heat insulation above referred to.

Suitable provision is made for introducing and discharging water from the chambers Q, such as the ingress pipe T (Fig. 4) and the exit pipe U (Fig. 3). These pipes are screwed into the jacket 0 through holes which are made in the neck G. The pipes T and U are also indicated in Fig. 1. The water-jacket is preferably reinforced by plates V, at the connections of the pipes, as best illustrated in this figure.

By the construction just described the material which passes down through the funnel mouth L of the liner strikes a zone of coolness which so affects it as to permit it to be fed into the mixing chambers, and thus much facilitates the feed of the product.

. or otherwise. Preferably an insulating air space A is provided in this construction. In modifying the Banbury mixer for the purpose described,

it is, of course, desirable that the weight I shall be reduced in dimensions, so that it will fit thesmaller opening occasioned by the restriction of the normal capacity of the neck. It is also advisable in some instances to water-cool the weight to some extent, as by the passage Y,-

running part way around the neck and connected to inlet and outlet pipes Z Z.

While we have shown and described several forms of the invention, it will be understood that we do not wish to be limited thereto, since various changes may be made therein without departing from the spirit of the invention.

What we claim is:

1. A machine for plasticating phenol compounds or the like, comprising plasticating means, a feed opening, a passage leading from the feed opening to such plasticating means, and a separable liner for such passage, said liner being formed with water passages.

2. A machine for plasticating phenol compounds or the like, comprising plasticating means, a feed opening, a passage leading from the feed opening to such plasticating means, and a separable liner for such passage, said liner being formed with water passages, and comprising a casting fitting into said passage and a jacket fitted to the exterior of the casting and arranged between the latter and the wall of the feed passage. T

3. A machine for plasticating phenol compounds or the like, comprising plasticating means, a feed opening, a passage leading from the feed opening to such plasticating means, and

a separable liner for such passage, said linerbeing formed with water passages, and comprising a casting having a tapered top fitting in said passage, and a sheet metal jacket arranged about the exterior of said casting between the latter and the wall of the feed passage.

4. A machine for plasticating phenol compounds or the like, comprising two troughs, rotors in said troughs, a hopper above the troughs, and a neck between the hopper and the troughs, water-jacketing means arranged at said neck, and insulating means also arranged at the neck between the body of the machine and the material. I

5. A machine for plasticating phenol compounds or the like comprising plasticating means, a feed opening, a passage leading from the feed opening to such plasticating means, such passage being substantially spaced apart from, and largely heat insulated from the body of the machine on all sides of the passage.

6. A machine for plasticating phenol compounds or the like comprising plasticating means, a feed opening, a passage leading from the feed opening through such plasticating means, such passage being substantially spaced apart from, and largely heat insulated from the body of the machine, such insulation comprising an air space substantially surrounding the passage.

'7. A machine for plasticating phenol compounds comprising plasticating means, a feed opening, a water-cooled passage leading from the feed opening to such plasticating means, and means for substantially insulating such watercooled passage from the body of the machine.

8. A machine for plasticating phenol compounds comprising plasticating means, a feed opening, a water-cooled passage leading from the feed opening to such plasticating means, and means for substantially insulating such watercooled passage from the body of the machine,

a feed opening, a passage leading from the feed opening to such plasticating means, a separable liner for such passage, said liner being formed with water passages and comprising a casting fitting into said passage and a jacket fitted to the exterior of the casting and arranged between the latter and the wall of the feed passage, and said jacket being separated in large part from the wall of the feed passage to provide heat in sulating means for such liner.

DAVID A. DUCHARME.

FERNLEY H. BANBURY. 

